This invention concerns a mixer valve with a ball-type valving member provided with a control member for being displaced in rotation around two different axes, and provided with openings cooperating with inlet openings for hot and cold water, having tubular gaskets of elastomeric material, and with outlet openings for mixed water, provided in a partially spherical seat of a fixed member, in order to regulate the mixing ratio between hot and cold water and the flow of delivered mixed water.
The mixer valves of the mentioned type are popular because they offer different advantages, however they also have some disadvantages which result particularly from the relatively reduced useful diameter of the tubular gaskets of elastomeric material, through which enter the hot and the cold water. The limit to this useful diameter is mainly due to the limit to the allowable diameter of the ball valving member. More particularly, such valves have a limited flow, an excessively reduced socalled "comfort zone", namely the length of the control member stroke which corresponds to the more frequent controls, and a relatively high noise at the larger flows. Of course, the mentioned disadvantages could be reduced by using a larger useful diameter for the tubular gaskets, but it is not possible to increase said diameter beyond certain limits, on one hand because, for reasons of space, this would require an increase in the diameter of the ball valving member, and therefore of the entire valve, and on the other hand because beyond a certain size the gaskets of elastomeric material could lose their stability and would require to be pressed against the ball valving member by an excessively high force, which would cause friction and other disadvantages.